In brief:

add_action(‘wp_ajax_my_query’, ‘my_query_handler’);
function my_query_handler() {
// Pull input out of $_POST and spit out your JSON, XML, etc…
die; // die at the end so WP Core will cease trying to handle the request.
}

The above function would then be accessible via $blog_url . ‘/wp-admin/admin-ajax.php?action=my_query&…’.

For additional detail:
http://codex.wordpress.org/AJAX_in_Plugins

Do not follow these instructions. Instead study the codex carefully for the correct way of adding AJAX to your plugins: http://codex.wordpress.org/AJAX_in_Plugins

Basically I have installed a plugin to load some content in the page above. Very slow.

So I thought I could use the asynchronous load technique, using JQuery.

What i did is:
1) prepare a DIV container to hold injected data in index.php
2) invoke jQuery from index.php to load an external php file that will call the very slow function.

The problem is that it looks like the external php file loaded with jQuery ignores the Wordpress install, as it can’t “see” Wordpress; as a result when calling the function in the external php file, an error is issued: “Fatal error: Call to undefined function”.

I have attempted succesfully to load data into the placeholder, using the external php file, using “include” and/or “require” functions, so the external php file would do the job if only jQuery (or Javascript?) would be capable to “see” Wordpress data.

I have tried to declare

require_once(“../../../../wp-config.php”);

but I get some errors….

What do you think? Do you believe Javscript or jQuery are ignoring Wordpress, so this is why the invoked function is failing?

If so how to “inform” Javascript/jQuery to “see” WP?

Thanks